CN1623900A - Ammonia refining method and refining device - Google Patents

Abstract

The object of this invention is to provide an ammonia refining method for efficiently removing diversified kinds of non-metallic impurities included in raw material ammonia and simplifying a continuous refining process, and to provide an apparatus therefor. The gaseous ammonia refining apparatus of this invention refines the crude gaseous ammonia containing moisture and low boiling point gaseous impurities having a boiling point lower than that of the ammonia, and is equipped with: a distillation section 3 which consists of a heat exchanger into which the crude gaseous ammonia is introduced to liquefy the gaseous ammonia by using a cooling effect; an exhaust path which is disposed in the distillation section 3 and exhausts the low boiling point gaseous impurities in a gaseous state; a vaporizer which vaporizes the liquefied ammonia discharged from the distillation section 3; moisture adsorption sections 22 and 24 which adsorb the moisture; catalyst sections 23 and 25 which separate oxygen; and a gaseous ammonia introducing path which introduces the gaseous ammonia vaporized by the vaporizer into the moisture adsorption sections 22 and 24 and the catalyst sections 23 and 25.

Description

Ammonia refining method and refining device

technical field

The invention relates to a refining method for refining crude ammonia gas containing various impurities, and more specifically, relates to an ammonia refining method and a refining device for providing high-purity ammonia necessary for the semiconductor industry, chemical industry, and research institutes.

Background technique

Ammonia is generally used frequently in the semiconductor manufacturing industry and the like, and ammonia refined from raw material ammonia is used at the manufacturing site. Raw ammonia is ammonia synthesized by an ammonia production plant, or recycled ammonia recovered from the site of use, etc. This raw material ammonia contains non-metallic impurities such as water, hydrogen, oxygen, carbon monoxide, carbon dioxide, and methane in addition to metals, and must be refined into high-purity ammonia for use in semiconductor manufacturing and the like.

In the past, various studies have been conducted on the removal of impurities contained in the above raw material ammonia. For example, regarding the removal of water, Patent Document 1-JP-A-9-142833 discloses a method of removing water by bringing ammonia into contact with barium oxide. In addition, regarding carbon monoxide and carbon dioxide, Patent Document 2-JP-A-6-107412 discloses a method of removing ammonia by contacting it with a nickel catalyst.

However, as described above, since raw material ammonia contains many kinds of impurities, it is necessary to carry out the individual substance removal methods proposed in Patent Document 1 or Patent Document 2 or the like. Therefore, there arises a problem that many refining steps are required for refining ammonia. That is, in order to efficiently obtain a large amount of high-purity ammonia, continuous purification is necessary. When there are many individual refining steps, there is a problem that large-scale refining facilities are required for continuous refining.

Contents of the invention

A first object of the present invention is to provide an ammonia purification method and a purification apparatus thereof capable of efficiently removing various non-metallic impurities contained in raw ammonia without a multi-step purification process. In addition, the second object is to provide an ammonia purification method and a purification apparatus thereof which can efficiently remove impurities of water and oxygen and contribute to efficient continuous purification. In addition, a third object is to provide an ammonia purification method and a purification device that can efficiently remove various non-metallic impurities, can purify high-purity ammonia, and can simplify a continuous purification process.

The present invention is completed in order to solve the aforementioned problems. The first scheme of the present invention is a method for refining crude ammonia gas containing low-boiling impurity gases with a boiling point lower than ammonia, including: introducing the aforementioned After the crude ammonia gas, the ammonia gas is liquefied by the cooling effect of the heat exchanger, and the low-boiling impurity gas is directly exhausted in a gaseous state from the distillation unit, and the low-boiling impurity gas is removed from the crude ammonia gas.

A second aspect of the present invention is the method for refining ammonia gas according to the first aspect, wherein a liquefied ammonia storage section for storing liquefied ammonia is provided in the distillation section, and the liquefied ammonia in the liquefied ammonia storage section is heated to exhaust and remove the liquefied ammonia. Low-boiling impurities remaining in liquefied ammonia.

A third aspect of the present invention is the method for purifying ammonia according to the first or second aspect, wherein the liquefied ammonia is discharged from the liquefied ammonia storage unit and passed through a heating unit to be vaporized.

A fourth aspect of the present invention is a method for purifying crude ammonia gas containing at least moisture and oxygen, comprising introducing the crude ammonia gas into a moisture adsorption unit that absorbs moisture and a catalyst unit that separates oxygen, and removing moisture from the crude ammonia gas. with oxygen.

A fifth aspect of the present invention is a method for refining crude ammonia gas containing at least moisture and oxygen, including setting at least a pair of moisture adsorption parts for adsorbing moisture and a catalyst part for separating oxygen. The crude ammonia gas is introduced into the catalyst part, moisture and oxygen are removed from the crude ammonia gas, and on the other hand, a reducing gas is passed into the other moisture adsorption part and the catalyst part for regeneration.

A sixth aspect of the present invention is the method for purifying ammonia gas according to the aforementioned fifth aspect, wherein the removal of moisture and oxygen from the crude ammonia gas, And the continuous refining is carried out by the regeneration by feeding the aforementioned reducing gas.

The seventh aspect of the present invention is a method for refining crude ammonia gas containing moisture and a low-boiling impurity gas having a lower boiling point than ammonia, including a first removal step, a gasification step, and a second removal step. In a removal process, the aforementioned crude ammonia gas is introduced into the distillation section composed of a heat exchanger, the ammonia gas is liquefied by the cooling effect of the heat exchanger, and the aforementioned low-boiling point impurity gas is directly exhausted in a gaseous state from the aforementioned distillation section, The low-boiling-point impurity gas is removed from the crude ammonia gas. In the gasification step, the ammonia liquefied in the distillation part is discharged from the distillation part, passed through the heating part, and gasified. In the second removal step In the process, the ammonia gas gasified in the gasification step is introduced into the moisture adsorption part that absorbs moisture and the catalyst part that separates oxygen, and moisture and oxygen are removed from the ammonia gas.

An eighth aspect of the present invention is the ammonia gas purification method of the aforementioned seventh aspect, which includes a third removal step, and in the third removal step, a liquefied ammonia storage unit for storing ammonia liquefied in the first removal step is provided. , by heating the liquefied ammonia in the liquefied ammonia storage part and exhausting the gas to remove remaining low-boiling impurities in the liquefied ammonia, and introducing the liquefied ammonia into the aforementioned gasification step through the aforementioned third removal step to be vaporized.

The ninth aspect of the present invention is the ammonia purification method of the aforementioned seventh or eighth aspect, wherein the aforementioned second removal process includes removal treatment and regeneration treatment, and in the removal treatment, at least one pair of aforementioned moisture adsorption The moisture adsorbing portion and the catalyst portion of one of the catalyst portion and the catalyst portion introduce the ammonia gas vaporized in the gas step to remove moisture and oxygen from the ammonia gas. The adsorption part and the aforementioned catalyst part are regenerated by introducing reducing gas.

A tenth aspect of the present invention is the method for purifying ammonia gas according to the ninth aspect, wherein the removal of moisture and oxygen and the introduction of the oxygen are alternately repeated for each of the pair of the aforementioned moisture adsorption section and the aforementioned catalyst section. Continuous refining is carried out in conjunction with the aforementioned regeneration treatment of the aforementioned reducing gas.

An eleventh aspect of the present invention is the ammonia purification method according to any one of the first to tenth aspects, wherein the crude ammonia gas is a gaseous component gas obtained by separating raw ammonia into a liquid phase and a gaseous phase.

A twelfth aspect of the present invention is a refining device for refining crude ammonia gas containing a low-boiling impurity gas having a boiling point lower than that of ammonia, and has a distillation unit composed of a heat exchanger that liquefies the ammonia gas by cooling after introducing the crude ammonia gas. In the distillation section, an exhaust passage for directly exhausting the low-boiling point impurity gas in a gaseous state is provided in the distillation section.

A thirteenth aspect of the present invention is the ammonia purification device according to the twelfth aspect, wherein the distillation unit includes a liquefied ammonia storage unit for storing liquefied crude ammonia and separates the low-boiling-point impurities from the liquefied ammonia in the liquefied ammonia storage unit. Gas heating device.

A fourteenth aspect of the present invention is the ammonia purification device according to the twelfth or thirteenth aspect, further comprising a vaporizer for vaporizing the liquefied ammonia discharged from the distillation unit.

A fifteenth aspect of the present invention is a refining device for refining crude ammonia gas containing at least moisture and oxygen, comprising a moisture adsorption unit for absorbing moisture and a catalyst unit for separating oxygen, and the crude ammonia is introduced into the moisture adsorption unit and the catalyst unit. Gas, remove moisture and oxygen from the aforementioned crude ammonia gas.

A sixteenth aspect of the present invention is a refining device for refining crude ammonia gas containing at least moisture and oxygen, which has at least a pair of moisture adsorption parts for adsorbing moisture and a catalyst part for separating oxygen, and is provided with an The catalyst part introduces a crude ammonia gas introduction passage for introducing the crude ammonia gas, and a reducing gas introduction passage for introducing a reducing gas into each of the moisture adsorption part and the catalyst part, and the crude ammonia passes through one of the moisture adsorption part and the catalyst part. The crude ammonia gas is introduced into the gas introduction passage to remove moisture and oxygen from the crude ammonia gas, and on the other hand, a reducing gas is introduced into the other moisture adsorption part and the catalyst part through the reducing gas introduction passage for regeneration.

A seventeenth aspect of the present invention is the ammonia purification device according to the sixteenth aspect, which has a continuous refining control unit that controls the switching of the crude ammonia gas introduction passage and the reducing gas introduction passage, so that the pair of the moisture adsorption unit and the catalyst Removal of moisture and oxygen from the crude ammonia gas and regeneration by introducing the reducing gas are repeated alternately in each part.

An eighteenth aspect of the present invention is a refining device for refining crude ammonia gas containing moisture and a low-boiling impurity gas having a lower boiling point than ammonia, and has a heat exchanger configuration for liquefying the ammonia gas by cooling after introducing the crude ammonia gas. The distillation section of the distillation section, the exhaust passage provided in the distillation section to directly exhaust the low-boiling impurity gas in a gaseous state, the gasification device for vaporizing the liquefied ammonia discharged from the distillation section, the moisture adsorption section for absorbing moisture, and the separation A catalyst part for oxygen, and an ammonia gas introduction passage for introducing ammonia gas vaporized by the gasification device into the moisture adsorption part and the catalyst part.

A nineteenth aspect of the present invention is the ammonia purification device according to the eighteenth aspect, wherein a liquefied ammonia storage section for storing the crude ammonia liquefied in the distillation section is provided in the distillation section, and the liquefied ammonia storage section includes A heating device for low-boiling-point impurities in liquefied ammonia in the liquefied ammonia storage unit.

A twentieth aspect of the present invention is the ammonia purification device according to the eighteenth or nineteenth aspect, wherein at least one pair of the aforementioned moisture adsorption unit and the aforementioned catalyst unit are provided, and the aforementioned gas for introduction is provided in each of the aforementioned moisture adsorption unit and the aforementioned catalyst unit. The ammonia gas introduction passage for the ammonia gas vaporized by the gasification device is provided, and a reducing gas introduction passage for introducing a reducing gas is provided in each of the moisture adsorption part and the catalyst part, and the ammonia is passed through one of the moisture adsorption part and the catalyst part. The gas introduction passage introduces the vaporized ammonia gas, removes moisture and oxygen from the ammonia gas, and regenerates the other moisture adsorbing part and the catalyst part by passing a reducing gas through the reducing gas introduction passage.

A twenty-first aspect of the present invention is the ammonia purification device according to the twenty-first aspect, wherein a continuous purification control unit for controlling the switching of the ammonia gas introduction passage and the reducing gas introduction passage is provided so that the pair of the moisture adsorption unit and the Removal of moisture and oxygen from the crude ammonia gas and regeneration by passing the reducing gas are alternately repeated in each part of the catalyst part.

A twenty-second aspect of the present invention is the ammonia purification device according to any one of the twelfth to twenty-first aspects, wherein the crude ammonia gas is a gas-phase component gas obtained by separating raw ammonia into a liquid phase and a gas phase.

If adopt the ammonia purification method of the first scheme of the present invention, then can after the distillation part that heat exchanger constitutes introduces crude ammonia gas, utilize the cooling action of aforementioned heat exchanger to ammonia gas is liquefied, by boiling point ratio from the aforementioned distillation part The low-boiling-point impurity gas low in ammonia is directly exhausted in a gaseous state, and the low-boiling-point impurity gas is removed from the crude ammonia gas.

In addition, the rough ammonia gas in this invention is raw material ammonia of a gaseous state. In addition, the above-mentioned low-boiling impurity gas having a boiling point lower than that of ammonia is hydrogen (H ₂ ), oxygen (O ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrogen (N ₂ ), methane (CH ₄ ) etc.

If the refining method of the second aspect of the present invention is adopted, in the aforementioned first aspect, a liquefied ammonia storage part for storing liquefied ammonia can be set in the aforementioned distillation part, and the liquefied ammonia in the liquefied ammonia storage part can be heated to discharge the liquefied ammonia. The low-boiling impurities remaining in the liquefied ammonia can be removed by using gas, so that higher-purity ammonia can be refined.

If the refining method of the third aspect of the present invention is adopted, in the aforementioned first or second aspect, after the liquefied ammonia is discharged from the aforementioned liquefied ammonia storage part, it is then gasified by the heating part, so the aforementioned first ammonia can be discharged in a gaseous state. The high-purity refined ammonia in the 1st or 2nd scheme is supplied to the continuous process.

According to the purification method according to the fourth aspect of the present invention, crude ammonia gas can be introduced into the moisture adsorption section for absorbing moisture and the catalyst section for separating oxygen, and at least moisture and oxygen as non-metallic impurities can be removed from the crude ammonia gas. In addition, in the catalyst part of the present invention, for example, if a nickel catalyst is used, not only oxygen but also carbon monoxide (CO) can be removed. The use of this nickel catalyst exhibits the same removal effect also in the catalyst part of the following embodiment of the present invention. In addition, molecular sieves, activated alumina, and the like are preferable as the moisture adsorbent used in the moisture adsorbing portion of the present invention.

If the refining method of the fifth aspect of the present invention is adopted, since at least one pair of moisture adsorption section for absorbing moisture and a catalyst section for separating oxygen are set, crude ammonia gas is introduced into one of the aforementioned moisture adsorption section and the aforementioned catalyst section, and the crude ammonia gas is obtained from the aforementioned crude ammonia gas. At least moisture and oxygen as non-metallic impurities are removed in the medium, and on the other hand, a reducing gas is passed through the other aforementioned moisture adsorption portion and the aforementioned catalyst portion for regeneration, so the regeneration of moisture and oxygen can be performed continuously without interruption. Removing the treatment can improve the refining efficiency of high-purity ammonia. As the reducing gas used for regeneration, a mixed gas of hydrogen and nitrogen or a mixed gas of hydrogen and self-refined ammonia is used.

If the purification method of the sixth aspect of the present invention is adopted, in the aforementioned fifth aspect, the removal of moisture and oxygen of the aforementioned crude ammonia gas and the aforementioned passage are repeated alternately to each part of the pair of the aforementioned moisture adsorption portions and the aforementioned catalyst portions. Continuous refining is carried out through the regeneration of the incoming reducing gas, so a large amount of high-purity ammonia can be refined.

If the refining method of the seventh aspect of the present invention is adopted, since the first removal step, the gasification step and the second removal step are included, in the first removal step, the distillation part containing water and boiling point ratio is introduced into the distillation part composed of a heat exchanger. The crude ammonia gas of the low-boiling point impurity gas with low ammonia is liquefied by the cooling effect of the heat exchanger, and the low-boiling impurity gas is directly exhausted in a gaseous state from the distillation part to remove it from the crude ammonia gas. In the gasification step, the low-boiling point impurity gas is discharged from the distillation unit to discharge ammonia liquefied in the distillation unit, and is vaporized by passing through the heating unit. The adsorption part and the catalyst part for separating oxygen introduce the ammonia gas gasified in the aforementioned gasification step, and remove moisture and oxygen from the ammonia gas, so that the first removal step can be used to remove low-boiling impurity gases with a lower boiling point than ammonia, or Water and oxygen are removed by the second removal step through the aforementioned gasification step, and the continuous treatment of impurities can be realized to refine higher-purity ammonia.

If the purification method according to the eighth aspect of the present invention is adopted, since the above-mentioned seventh aspect includes providing a liquefied ammonia storage part for storing the ammonia liquefied in the first removal step, and heating the liquefied ammonia in the liquefied ammonia storage part. The third removal process of removing the low-boiling point impurities remaining in the liquefied ammonia by exhaust gas, the liquefied ammonia is introduced into the aforementioned gasification process through the aforementioned third removal process to make it gasified, so the aforementioned third removal process can also be used to remove the The low-boiling point impurities remaining in the first removal step can also improve the purification purity.

According to the purification method according to the ninth aspect of the present invention, in the aforementioned seventh or eighth aspect, the aforementioned second removal step includes at least one pair of the aforementioned moisture adsorbing portion and the aforementioned catalyst portion being provided in the aforementioned moisture adsorbing portion and the aforementioned The catalyst part introduces the ammonia gas gasified in the gasification step to remove moisture and oxygen from the ammonia gas, and the regeneration process passes a reducing gas into the other moisture adsorption part and the catalyst part to regenerate. In the second removal step, by regenerating at least one of the moisture adsorption unit and the catalyst unit, continuous purification is possible without interrupting the continuous steps from the first to second removal steps by the regeneration operation.

If the purification method according to the tenth aspect of the present invention is adopted, in the aforementioned ninth aspect, the aforementioned removal of moisture and oxygen and the aforementioned introduction of the reducing gas are repeated alternately to each part of the aforementioned pair of the aforementioned moisture adsorption portions and the aforementioned catalyst portions. Continuous refining is carried out through the aforementioned regeneration treatment, so a large amount of high-purity ammonia can be refined.

If the refining method of the eleventh scheme of the present invention is adopted, since the aforementioned crude ammonia gas uses the gaseous phase component gas obtained by separating the raw material ammonia into a liquid phase and a gaseous phase, the liquid phase contains a large amount of water and metal impurities, and the water and metal Gas-phase ammonia with a very small content of quasi-impurity parts is used as the starting material for refining, and ammonia with higher purity can be refined by implementing the refining method of any one of the above-mentioned schemes 1 to 10 for refining treatment.

If the ammonia refining device of the twelfth aspect of the present invention is adopted, after the crude ammonia gas is introduced into the distillation part constituted by the heat exchanger, the ammonia gas is liquefied by the cooling action of the heat exchanger, and the ammonia gas is liquefied from the distillation part through the exhaust passage. The low-boiling impurity gas having a boiling point lower than that of ammonia is directly exhausted in a gaseous state, and the low-boiling impurity gas can be removed from the crude ammonia gas.

According to the refining device according to the thirteenth aspect of the present invention, in the aforementioned twelfth aspect, a liquefied ammonia storage section for storing liquefied ammonia is provided in the distillation section, and the liquefied ammonia in the liquefied ammonia storage section is heated by using the heating device, The low-boiling impurities remaining in the liquefied ammonia can be removed by exhaust gas, and higher-purity ammonia can be refined.

If the refining device of the fourteenth aspect of the present invention is adopted, after the liquefied ammonia is discharged from the aforementioned liquefied ammonia storage part, the aforementioned gasification device is used to gasify the liquefied ammonia, so the aforementioned twelfth or thirteenth aspect can be used to discharge high-purity refined ammonia in a gaseous state. The ammonia can be supplied to the continuous process.

According to the purification device according to the fifteenth aspect of the present invention, the crude ammonia gas can be introduced into the moisture adsorption part for absorbing moisture and the catalyst part for separating oxygen, and at least moisture and oxygen as non-metallic impurities can be removed from the crude ammonia gas.

According to the refining device according to the sixteenth aspect of the present invention, at least one pair of moisture adsorption unit for absorbing moisture and catalyst unit for separating oxygen are provided, and crude ammonia gas is introduced into one of the moisture adsorption unit and the catalyst unit through the crude ammonia gas introduction passage. , remove at least moisture and oxygen as non-metallic impurities from the aforementioned crude ammonia gas, and on the other hand, regenerate by passing a reducing gas into the other aforementioned moisture adsorbing part and the aforementioned catalyst part through the aforementioned reducing gas introduction path, so regeneration can be used. The removal of moisture and oxygen is carried out continuously without interruption, improving the efficiency of refining high-purity ammonia.

According to the refining device according to the 17th aspect of the present invention, in the aforementioned 16th aspect, by using the aforementioned continuous refining control section to control the switching of the aforementioned rough ammonia gas introduction passage and the aforementioned reducing gas introduction passage, the pair of aforementioned moisture adsorption sections can Removal of moisture and oxygen from the crude ammonia gas and regeneration by passing the reducing gas are repeated alternately with each part of the catalyst part, and continuous purification is carried out to realize large-scale purification of high-purity ammonia.

If the refining device according to the eighteenth aspect of the present invention is adopted, through the aforementioned distillation section and the aforementioned exhaust passage provided in the aforementioned distillation section, the aforementioned low-boiling point impurity gas is directly exhausted in a gaseous state, and the gas containing moisture and a boiling point lower than ammonia is exhausted. Crude ammonia gas liquefaction of low-boiling point impurity gas can directly remove the above-mentioned low-boiling point impurity gas from the gaseous state from the above-mentioned distillation part. In addition, since the liquefied ammonia is vaporized by using the above-mentioned gasification device through the above-mentioned ammonia gas introduction passage The ammonia gas is introduced into the moisture adsorption part and the catalyst part, and moisture and oxygen can be removed from the ammonia gas, so that the continuous treatment process of impurities can be realized, and higher purity ammonia can be refined.

According to the refining device according to the nineteenth aspect of the present invention, in the above-mentioned eighteenth aspect, a liquefied ammonia storage part for storing liquefied ammonia is provided, and the liquefied ammonia in the liquefied ammonia storage part can be separated and removed by using the aforementioned heating device. Low-boiling impurities remaining in liquefied ammonia, so it can improve the purity of refining.

According to the refining device according to the twentieth aspect of the present invention, in the aforementioned eighteenth or nineteenth aspect, since the aforementioned moisture adsorption portion and the aforementioned catalyst portion of one of the at least one pair of the aforementioned moisture adsorption portion and the aforementioned catalyst portion are provided with the aforementioned ammonia gas The introduction passage introduces the ammonia gas vaporized by the gasification device, removes moisture and oxygen from the ammonia gas, and regenerates the other moisture adsorption part and the catalyst part by passing a reducing gas through the reducing gas introduction passage. In parallel with the removal treatment by one of the moisture adsorption unit and the catalyst unit, the regeneration treatment of the other moisture adsorption unit and the catalyst unit is performed, so that continuous purification can be performed without interrupting the removal process by regeneration.

According to the refining device according to the twenty-first aspect of the present invention, in the twenty-first aspect, by using the continuous refining control section to control the switch of the crude ammonia gas introduction passage and the reduction gas introduction passage, it is possible to control the pair of the moisture adsorption section and the reducing gas introduction passage. Each part of the catalyst part alternately repeats the removal of moisture and oxygen from the crude ammonia gas and the regeneration by passing the reducing gas into it for continuous purification, so that a large amount of high-purity ammonia can be purified.

In the 22nd scheme of the present invention, since the above-mentioned crude ammonia gas uses the gas phase component gas obtained by separating the raw material ammonia into a liquid phase and a gas phase, it utilizes the property that the liquid phase contains a large amount of water and metal impurities, and the partial content of water and metal impurities Very little gas-phase ammonia is used as a refining starting material, and ammonia of higher purity can be refined by implementing the refining method of any one of the aforementioned 12th to 21st schemes for refining treatment.

Description of drawings

Fig. 1 is a schematic configuration diagram of a refining apparatus of the present invention.

Fig. 2 is a schematic configuration diagram of another refining device of the present invention.

Fig. 3 is a schematic configuration diagram of still another refining device of the present invention.

Fig. 4 is an analysis chart of impurity concentration for illustrating the refining effect of the present invention.

Fig. 5 is a distribution diagram of ammonia usage amount-gas phase water concentration for explaining an appropriate ammonia usage state in the refining apparatus of Fig. 3 .

Detailed ways

Hereinafter, embodiments of the ammonia purification method and purification apparatus of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1 , a refining device and a refining method for removing low-boiling impurities from crude ammonia according to the present invention will be described. Fig. 1 is a schematic configuration diagram of a refining apparatus according to this embodiment. The raw material ammonia is contained in the liquid ammonia container 1, and the ammonia gas in the gas phase part 12 becomes crude ammonia gas for purification. The raw material ammonia is separated into a liquid phase part 11 and a gas phase part 12 , and since the liquid phase and the gas phase are separated, moisture and metal impurities contained in the raw material ammonia basically remain in the liquid phase part 11 . Therefore, the ammonia in the gas phase part 12 obtained by the separation of the liquid phase and the gas phase is in the state of pre-removal of moisture and metal impurities, so it is transferred to the refining process in this state. As the starting material ammonia, it is suitable for higher Purity and refinement of raw materials used.

A distillation column 2 for removing various non-metallic impurities contained in the crude ammonia gas, a distillation section 3 composed of a heat exchanger 31 located at the upper part of the column, a gas inflow section 7 located at the middle section, and a gas inflow section 7 located at the lower section. The liquefied ammonia storage unit 8 is constituted. The heat exchanger 31 of the distillation unit 3 is connected to the refrigerant circulation device 4 through the refrigerant supply circulation paths 41 and 42 , and the refrigerant is circulated and supplied to the heat exchanger 31 . Ethylene glycol is used as the refrigerant, and a temperature sensor monitoring system (not shown) provided on the refrigerant circulation device 4 is used to keep the inside of the heat exchanger 31 at -5°C to +10°C. A plurality of gas passages 32 of the heat exchanger 31 are formed in communication between the gas inflow portion 7 and the uppermost space 6 of the distillation column 2 . The gas inflow part 7 communicates with the gas phase part 12 of the liquid ammonia container 1 through the gas supply passage 9 , and the crude ammonia gas from the gas phase part 12 is supplied through the gas supply passage 9 . Since the crude ammonia gas supplied to the gas inflow part 7 enters the gas passage 32 and is liquefied by the cooling effect of the heat exchanger 31 and the refrigerant circulation device 4, it forms liquid droplets in the liquefied ammonia storage part 8 at the bottom of the distillation tower 2 and falls to liquefy. Ammonia is stored. On the other hand, in the uppermost space 6, when the crude ammonia in the distillation unit 3 is liquefied, the impurity gas with a low boiling point accumulates together with a part of the ammonia gas, passes through the exhaust passage 10 provided in the uppermost space 6, and is exhausted by an exhaust device (not included). As shown in the figure), the impurity gas can be discharged. At this time, the impurity gases accumulated in the uppermost space 6 are mainly hydrogen (H ₂ ), oxygen (O ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrogen (N ₂ ), methane (CH ₄ ) and the like.

If the above-mentioned distillation part 3 is adopted, since the crude ammonia gas is liquefied, the liquefied ammonia 81 is stored in the liquefied ammonia storage part 8, and non-metallic impurities having a boiling point lower than ammonia are separated as gas, so the uppermost space 6 can be Separation and recovery of impurity gases can remove a variety of impurities at one time. Therefore, separate removal steps for impurities such as hydrogen, oxygen, carbon monoxide, carbon dioxide, nitrogen, and methane are not required, and high purification of ammonia can be realized simply and efficiently using a single distillation column 2 .

The distillation column 2 also has the function of exhausting residual impurities to realize high purification of ammonia. That is, the liquefied ammonia storage unit 8 is provided with a warm water circulation pipe 13 for circulating the warm water supplied from the warm water circulation device 5 in the storage unit. The warm water is kept at 30° C. to 50° C. by a temperature sensor monitoring system (not shown) provided in the warm water circulation device 5 , and boiling (vaporization) occurs on the surface of the warm water circulation pipe 13 by the warm water circulation. Therefore, impurities remaining during the liquefaction of the crude ammonia in the distillation unit 3 are separated from the liquid ammonia, discharged to the side of the gas inflow unit 7 , and finally recovered in the uppermost space 6 .

Since the heating function of the heating device composed of the above-mentioned warm water circulation device 5 and warm water circulation piping 13 is given to the liquefied ammonia storage part 8, impurities remaining in the ammonia liquefied by the distillation part 3 can also be removed, and the ammonia yield can be further improved. Refined purity.

The liquid ammonia stored in the liquefied ammonia storage unit 8 is discharged to the gasification unit 15 side through the discharge passage 14 . The vaporizer 15 is arranged in the warm water tank 16 . A heater 18 is built in the warm water tank 16, and the warm water state is controlled at 30° C. to 100° C. by the constant temperature control unit 17 . Therefore, the liquid ammonia discharged through the discharge passage 14 is vaporized by the vaporization device constituted by the warm water tank 16 in the vaporization part 15, and returns to a gaseous state. The regasified and refined ammonia gas can be discharged through the gasification part 15 by using an exhaust device (not shown), so as to obtain high-purity ammonia gas.

Hereinafter, a refining device capable of efficiently removing moisture and oxygen contained in crude ammonia and a refining method thereof will be described with reference to FIG. 2 . Fig. 2 is a schematic configuration diagram of a refining device according to this embodiment. The refining device of this embodiment is constituted by a pair of water, oxygen, and carbon monoxide removal units 20 and 21 . The water, oxygen, and carbon monoxide removal units 20 and 21 respectively have a water removal unit 22 and a catalyst unit 23 , and a water removal unit 24 and a catalyst unit 25 . Moisture removal units 22 and 24 are filled with molecular sieves composed of crystalline zeolite that absorb moisture. The water removal units 22 and 24 remove water by the adsorption of molecular sieves. As the moisture adsorbent, besides molecular sieves, moisture adsorbents such as activated alumina can also be used. The catalyst parts 23 and 25 are filled with a nickel catalyst. Oxygen and carbon monoxide are adsorbed and removed in the catalyst parts 23 and 25 by chemical adsorption of the nickel catalyst. The removal of oxygen and carbon monoxide impurities using a nickel catalyst proceeds through the following chemical reactions.

Each of the water, oxygen, and carbon monoxide removal units 20 and 21 forms a two-layer separation structure of a water removal unit and a catalyst unit. For example, when the amount of ammonia purification is 3N (standard state) m ³ /h, 0.3 kg of molecular sieves (filling height: 300 mm) are filled in each water removal part in a cylinder with an inner diameter of 43 mm. On the other hand, 0.8 kg of a nickel catalyst (filling height: 500 mm) was filled in each catalyst part. In addition, when ammonia gas is passed at a flow rate of 0.17 m/s in the filled state of these molecular sieves and nickel catalysts, the contact time with each adsorbent in the catalyst part and the moisture removal part is about 3 seconds and 1.77 seconds. In addition, the same adsorption effect can also be obtained by making the water, oxygen, and carbon monoxide removing parts 20 and 21 into a single hybrid structure in which a moisture adsorbent and a nickel catalyst are mixed.

The respective water, oxygen, and carbon monoxide removal units 20 and 21 introduce gas-phase ammonia gas from the liquid ammonia container 50 through the introduction passages 29 and 30 through the crude ammonia gas introduction passage 51 , respectively. The liquid ammonia container 50 has the same structure as the liquid ammonia container 1 used in the embodiment of FIG. 1 , and the moisture obtained by separating the raw material ammonia into liquid phase and gas phase and gaseous ammonia gas with less metal impurities are used as the gas to be purified.

In this device, the flow direction of the gas in the refining process (lower part → upper part) and the regeneration process (upper part → lower part) is designed to be reversed. However, the regeneration step can also be performed from the lower part to the upper part in the same manner as the refining step. Reference numerals 56 , 58 , and 59 denote on-off valves for introducing ammonia gas to the water, oxygen, and carbon monoxide removal units 20 , 21 . In addition, regeneration gas composed of hydrogen-reducing gas supplied from regeneration gas supply devices 54, 55 is supplied to water, oxygen, and carbon monoxide removal units 20, 21 through regeneration gas introduction side on-off valves 61, 64 through regeneration gas introduction passages.

An exhaust passage 28 is connected to the gas discharge passages 26 and 27 from the respective water, oxygen and carbon monoxide removal units 20 and 21, and gas discharge side on-off valves 62 and 63 are provided in the gas discharge passage. Furthermore, regeneration gas recovering devices 52 and 53 are provided for feeding regeneration gas from regeneration gas supply devices 54 and 55 to the water, oxygen, and carbon monoxide removal parts, and recovering the regeneration gas. On-off valves 57 and 60 for recovering regeneration gas are disposed in the recovery-side passage.

As the regenerating gas, hydrogen was used as a reducing gas for the nickel catalyst, and dry nitrogen was used to remove moisture from the molecular sieve. Therefore, hydrogen and nitrogen are introduced as regeneration gases. Heaters 70 and 71 are provided in each water, oxygen, and carbon monoxide removal section for heat treatment during regeneration. As an example of the regeneration process, at first, dry nitrogen gas is supplied to the water, oxygen, and carbon monoxide removal part by the regeneration gas supply device 54 or 55, and water, oxygen, and carbon monoxide are removed for 1 hour, and the water, oxygen, and carbon monoxide are removed by the heaters 70, 71 The carbon monoxide removal part is heated to about 200°C. Next, in this heated state, in addition to supplying dry nitrogen gas from the regeneration gas supply device 54 or 55, hydrogen gas was also supplied, and the reduction treatment of the nickel catalyst was performed for 3 hours. The reduction treatment of the nickel catalyst is performed by the following chemical reaction.

Then, it was switched to supplying only dry nitrogen gas, and the removal of adsorbed moisture was performed for 2 hours. Finally, the heating of the heaters 70 and 71 was gradually reduced while passing dry nitrogen gas, and the temperature returned to normal temperature in about 5 hours. In addition, for the supply of regeneration gas, for example, when the amount of ammonia purification is 3N (standard state) m ³ /h, the amount of reduced hydrogen gas can also be 4N (standard state) L/h when the dry nitrogen gas amount is 200N (standard state) L/h. )L/h. In addition, after the regeneration treatment is completed, if the purified ammonia gas is circulated for a certain period of time before refining without immediately transferring to refining, the adsorption effect will be good.

With the above configuration, since a pair of water, oxygen, and carbon monoxide removal units 20, 21 are used, one can be used for impurity removal treatment while the other can be used for regeneration treatment. Using a purification management and control device (not shown), for example, open the gas introduction side valves 56 and 58 from the state of closing all valves, and then open the exhaust side valve 62 to introduce crude ammonia into the water, oxygen, and carbon monoxide removal unit 20. Due to the introduction of crude ammonia, the nickel catalyst is used to remove oxygen and carbon monoxide impurities in the catalyst part 23, and the moisture impurities are removed by molecular sieve adsorption in the moisture removal part 22, and the refined ammonia gas obtained by continuously removing water, oxygen and carbon monoxide passes through the exhaust gas. Passage 28 is vented.

In addition, when the purification process on the side of the water, oxygen, and carbon monoxide removal unit 20 is completed, the valves 58 and 62 are closed. Open the valves 59 and 63 again, introduce crude ammonia to the water, oxygen, and carbon monoxide removal unit 21, and use the catalyst unit 25 and the water removal unit 24 to carry out subsequent refining treatment. On the other hand, the above-mentioned regeneration treatment is performed by opening the valves 57 and 61 in the water, oxygen, and carbon monoxide removal unit 20 that has been purified. In this way, by alternately switching each water, oxygen, and carbon monoxide removal unit to purification and regeneration, the continuous purification of high-purity ammonia can be realized by removing impurities in water and oxygen, and large-scale purification is possible.

Hereinafter, a refining apparatus capable of efficiently removing various impurities contained in crude ammonia and a refining method thereof will be described with reference to FIG. 3 . Fig. 3 is a schematic configuration diagram of a refining device according to this embodiment. In addition, in this embodiment, the same code|symbol is used for the same structure as embodiment of FIG.1 and FIG.2.

The refining device of this embodiment is composed of a distillation column 2 for removing various non-metallic impurities contained in the crude ammonia gas, and a pair of water, oxygen, and carbon monoxide removal units 20 and 21 for removing impurities of water, oxygen, and carbon monoxide. . The distillation column 2 and the water, oxygen, and carbon monoxide removal units 20 and 21 have the same structures as those described in FIG. 1 and FIG. 2 , respectively. In addition, in this embodiment, the raw material ammonia is also separated into a liquid phase part 11 and a gas phase part 12 in the liquid ammonia container 1, and the gaseous phase ammonia is exhausted from the gas phase part 12, and is introduced into the distillation tower 2 as crude ammonia gas. 19 is the gas phase part 12 An on-off valve between the gas supply passage 9 and the gas inflow portion 7 .

As described above, the distillation column 2 is composed of the distillation part 3, the gas inflow part 7 provided in the middle part, and the liquefied ammonia storage part 8 provided in the lower part. Since the crude ammonia gas is liquefied by the liquefaction function of the distillation unit 3, and the liquefied ammonia is stored in the liquefied ammonia storage unit 8, the non-metallic impurities having a lower boiling point than ammonia are separated as gases. The upper space 6 can separate and recover impurity gases, and can remove multiple types of impurity gases G1 at one time by exhausting through the exhaust passage 10 . The impurity gases accumulated in the uppermost space 6 are mainly hydrogen (H ₂ ), oxygen (O ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrogen (N ₂ ), methane (CH ₄ ) and the like. In addition, by utilizing the heating effect of the warm water circulation device 5 of the liquefied ammonia storage part 8 located at the lower part of the distillation tower 2, the impurities remaining during the liquefaction of crude ammonia in the distillation part 3 are also separated from the liquid ammonia and discharged to the side of the gas inflow part 7, Finally, it is recovered in the uppermost space 6, and the refined purity can be further improved.

The liquefied ammonia stored in the liquefied ammonia storage unit 8 is introduced into the water, oxygen and carbon monoxide removal units 20 and 21 sides through the warm water tank 16 through the discharge passage 14 . The liquid ammonia is gasified again by passing through the warm water tank 16, and introduced to the side of the water, oxygen, and carbon monoxide removal units 20 and 21 as secondary gas to be purified. Each water, oxygen, and carbon monoxide removal unit 20 , 21 has a water removal unit 22 , a catalyst unit 23 , and a water removal unit 24 and a catalyst unit 25 . Moisture removal is carried out in the moisture removal parts 22 and 24 by the adsorption action of the filled molecular sieves. The catalyst parts 23 and 25 adsorb and remove oxygen and carbon monoxide by the chemisorption action of the filled nickel catalyst. Therefore, in each water, oxygen, carbon monoxide removing part 20,21 can further remove the water, oxygen, carbon monoxide impurities that have not been treated cleanly in the distillation tower 2, finally adopt two steps to obtain more removal of various impurities through the exhaust passage 28 , especially high-purity refined ammonia G2 with water, oxygen and carbon monoxide impurities.

As described above, in the purification apparatus of this embodiment, a simpler high-purity purification process can be realized by connecting the distillation column 2 and the water, oxygen, and carbon monoxide removal units 20 and 21 as a purification system. In addition, as mentioned above, since a pair of water, oxygen, and carbon monoxide removal units 20 and 21 are used to alternately switch between refining and regeneration, one can always be operated for refining treatment, so the use of water, oxygen, and carbon monoxide removal units can be avoided. Refining treatment at the time of regeneration in parts 20 and 21 is interrupted, and continuous refining operation is possible, so it contributes to cost reduction of a large amount of refining.

Fig. 4 shows an example of measurement of impurity concentration distribution showing the refining effect of the above-mentioned refining device. First, the crude ammonia gas in the gas phase section 12 contains a large amount of hydrogen (H ₂ ), oxygen (O ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrogen (N ₂ ), and methane (CH ₄ ) in ppm order concentration units. low-boiling-point impurities and water (H ₂ O) (see (1) in FIG. 4 ). When the crude ammonia gas is purified by the distillation column 2, as shown in (3) of FIG. 4 , most impurities except water (H ₂ O) are reduced to a concentration unit of the ppb order. In addition, since the primary purified gas passed through the distillation tower 2 is introduced into the water, oxygen, and carbon monoxide removal units 20 and 21, water is also reduced to a concentration unit of the ppb level as shown in (4) of FIG. 4 . Therefore, according to the refining method using the refining device of this embodiment, purified ammonia of extremely high purity can be obtained. In addition, according to this measurement example, oxygen and carbon monoxide impurities are basically removed in the distillation column 2, and the amounts removed in stages by the water, oxygen, and carbon monoxide removal units 20 and 21 are extremely small.

In addition, as shown in (2) of Fig. 4, at first, since a large amount of water is contained in the liquid phase, the water in the gaseous ammonia is less than that in the liquid phase, but when the ammonia gradually decreases during continuous refining, water in the gaseous phase occurs A dramatic increase in content. Fig. 5 shows an example of measurement performed by the refining device of this embodiment. It can be seen from FIG. 5 that when the ammonia usage rate of the liquid ammonia container 1 reaches about 85%, the moisture in the gas phase increases sharply. Therefore, the usage of about 85% is generally the limit of purification, and if the purification device of this embodiment is used, it can be said that continuous purification up to 85% of ammonia usage is possible.

As mentioned above, with the refining method and refining device of the present invention, industrial raw material ammonia and the like can be refined with high purity, and the refining process can be simplified without using complicated refining steps, and a continuous refining process can also be easily formed.

Claims (22)

1. A method for refining ammonia, which is a method for refining crude ammonia gas containing a low-boiling impurity gas with a lower boiling point than ammonia, characterized in that, after the distillation part of the heat exchanger is used to import the crude ammonia gas, the aforementioned heat is used to The cooling action of the exchanger liquefies the ammonia gas, and the low-boiling impurity gas is directly exhausted in a gaseous state from the distillation unit to remove the low-boiling impurity gas from the crude ammonia gas. 2. The method for refining ammonia gas according to claim 1, characterized in that, a liquefied ammonia storage part for storing liquefied ammonia is set in the distillation part, and the liquefied ammonia in the liquefied ammonia storage part is heated to exhaust and remove residual ammonia. Low boiling impurities in liquefied ammonia. 3. The ammonia purification method according to claim 1 or 2, characterized in that the liquefied ammonia is discharged from the liquefied ammonia storage part and passed through a heating part to be vaporized. 4. A method for refining ammonia, which is a method for refining crude ammonia gas containing at least moisture and oxygen, characterized in that the crude ammonia gas is introduced into the moisture adsorption part for absorbing moisture and the catalyst part for separating oxygen, and the crude ammonia gas is obtained from the crude ammonia gas. Moisture and oxygen are removed from the gas. 5. A method for refining ammonia, which is a method for refining crude ammonia gas containing at least moisture and oxygen, characterized in that at least a pair of moisture adsorption parts for adsorbing moisture and catalyst parts for separating oxygen are set, on the one hand, in one side The moisture adsorbing part and the catalyst part introduce the crude ammonia gas to remove moisture and oxygen from the crude ammonia gas, and on the other hand, the other moisture adsorbing part and the catalyst part feed reducing gas for regeneration. 6. The method for refining ammonia gas according to claim 5, characterized in that, for each part of the pair of aforementioned moisture adsorption parts and the aforementioned catalyst part, the removal of moisture and oxygen of the aforementioned crude ammonia gas and the utilization of the gas are repeated alternately. Into the regeneration of the aforementioned reducing gas, so as to continuously refine. 7. A method for refining ammonia, which is a method for refining crude ammonia gas containing moisture and a low-boiling impurity gas having a lower boiling point than ammonia, and is characterized in that it includes a first removal process, a gasification process and a second removal process, In the first removal step, after the crude ammonia gas is introduced into the distillation section composed of a heat exchanger, the ammonia gas is liquefied by the cooling action of the heat exchanger, and the low-boiling impurity gas is directly vaporized from the distillation section. State exhaust, remove the aforementioned low-boiling point impurity gas from the aforementioned crude ammonia gas, in the gasification step, discharge the ammonia liquefied in the aforementioned distillation unit from the aforementioned distillation unit, make it pass through the heating unit to be vaporized, and In the second removal step, the ammonia gas vaporized in the aforementioned gasification step is introduced into the moisture adsorbing section that adsorbs moisture and the catalyst section that separates oxygen, and moisture and oxygen are removed from the ammonia gas. 8. The method for refining ammonia gas according to claim 7, characterized in that it includes a third removal step, in which a liquefied ammonia storage unit storing ammonia liquefied in the first removal step is provided, The low-boiling impurities remaining in the liquefied ammonia are removed by heating the liquefied ammonia in the liquefied ammonia storage unit, and the liquefied ammonia is introduced into the gasification step through the third removal step to be vaporized. 9. The method for refining ammonia according to claim 7 or 8, characterized in that, the aforementioned second removal step comprises removal treatment and regeneration treatment, and in said removal treatment, at least one pair of aforementioned moisture adsorption section and aforementioned The moisture adsorbing portion and the catalyst portion of one of the catalyst portions introduce the ammonia gas gasified in the gasification step to remove moisture and oxygen from the ammonia gas. In the regeneration process, the other moisture adsorbing portion and the catalyst portion The aforementioned catalyst part is regenerated by passing a reducing gas. 10. The method for purifying ammonia gas according to claim 9, characterized in that, for each part of the pair of the aforementioned moisture adsorption section and the aforementioned catalyst section, the aforementioned removal process of moisture and oxygen and the introduction of the aforementioned reduction process are repeated alternately. The aforementioned regeneration treatment of the gas is carried out continuously. 11. The method for refining ammonia according to any one of claims 1-10, characterized in that the crude ammonia gas is a gas phase component gas obtained by separating raw ammonia into a liquid phase and a gas phase. 12. Ammonia gas refining device, which is a refining device for refining crude ammonia gas containing a low-boiling impurity gas with a boiling point lower than ammonia, characterized in that it has the heat to liquefy the ammonia gas by cooling after introducing the crude ammonia gas The distillation section constituted by an exchanger is provided with an exhaust passage for exhausting the low-boiling point impurity gas directly in a gaseous state in the distillation section. 13. The ammonia refining device according to claim 12, wherein the distillation unit includes a liquefied ammonia storage unit for storing liquefied crude ammonia and is used to separate the low boiling point impurity gas from the liquefied ammonia in the liquefied ammonia storage unit. heating device. 14. The ammonia refining device according to claim 12 or 13, comprising a gasification device for gasifying the liquefied ammonia discharged from the distillation unit. 15. Ammonia gas purification device, which is a purification device for refining crude ammonia gas containing at least moisture and oxygen, characterized in that it has a moisture adsorption part for adsorbing moisture and a catalyst part for separating oxygen, and the moisture adsorption part and the catalyst part Partially introduce the aforementioned rough ammonia gas, and remove moisture and oxygen from the aforementioned rough ammonia gas. 16. Ammonia gas refining device, which is a refining device for refining crude ammonia gas containing at least moisture and oxygen, characterized in that it has at least a pair of moisture adsorption parts for adsorbing moisture and a catalyst part for separating oxygen, and each of the aforementioned moisture The adsorption unit and the catalyst unit are provided with a crude ammonia gas introduction channel for introducing the crude ammonia gas, and the respective moisture adsorption unit and the catalyst unit are provided with a reducing gas introduction channel for introducing a reducing gas. part introduces the aforementioned crude ammonia gas through the aforementioned crude ammonia gas introduction channel, and removes moisture and oxygen from the aforementioned crude ammonia gas. The gas is regenerated. 17. The ammonia gas refining device according to claim 16, characterized in that, there is a continuous refining control unit for controlling the switching of the aforementioned crude ammonia gas introduction passage and the aforementioned reducing gas introduction passage, so that for a pair of the aforementioned moisture adsorption unit and the aforementioned Removal of moisture and oxygen from the crude ammonia gas and regeneration by passing the reducing gas are alternately repeated in each part of the catalyst unit. 18. Ammonia gas refining device, which is a refining device for refining crude ammonia gas containing moisture and a low-boiling impurity gas with a lower boiling point than ammonia, characterized in that, after introducing the aforementioned crude ammonia gas, ammonia gas is liquefied by cooling The distillation part composed of a heat exchanger is provided in the exhaust passage of the above-mentioned distillation part to directly exhaust the aforementioned low-boiling point impurity gas in a gaseous state, and the gasification device for vaporizing the liquefied ammonia discharged from the aforementioned distillation part absorbs moisture. The moisture adsorption part, the catalyst part for separating oxygen, and the ammonia gas introduction passage for introducing the ammonia gas vaporized by the gasification device into the moisture adsorption part and the catalyst part. 19. The ammonia refining device according to claim 18, characterized in that a liquefied ammonia storage unit storing the crude ammonia liquefied in the distillation unit is located in the distillation unit, and the liquefied ammonia storage unit has a function for separating the crude ammonia remaining in the aforementioned distillation unit. A heating device for low-boiling-point impurities in liquefied ammonia in the liquefied ammonia storage unit. 20. The ammonia refining device according to claim 18 or 19, characterized in that, there is at least one pair of the aforementioned moisture adsorption unit and the aforementioned catalyst unit, and each of the aforementioned moisture adsorption unit and the aforementioned catalyst unit is provided with a gasification device leading into the aforementioned gasification device. The aforementioned ammonia gas introduction channel for ammonia gas, and a reducing gas introduction channel for introducing a reducing gas is provided in each of the aforementioned moisture adsorption part and the aforementioned catalyst part, and the aforementioned ammonia gas introduction channel is introduced into one of the aforementioned moisture adsorption part and the aforementioned catalyst part The vaporized ammonia gas removes moisture and oxygen from the ammonia gas, and regenerates the other moisture adsorption unit and catalyst unit by passing a reducing gas through the reducing gas introduction passage. 21. The ammonia gas refining device according to claim 20, characterized in that it has a continuous refining control unit that controls the switching of the aforementioned ammonia gas introduction passage and the aforementioned reducing gas introduction passage, so that the pair of the aforementioned moisture adsorption unit and the aforementioned catalyst unit Removal of moisture and oxygen from the aforementioned crude ammonia gas and regeneration of the aforementioned reducing gas are repeated alternately in each part. 22. The ammonia refining device according to any one of claims 12-21, characterized in that the crude ammonia gas is a gas phase component gas obtained by separating raw ammonia into a liquid phase and a gas phase.

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